New, traditionally non-fuel retailers are now selling fuel. These companies often have membership cards printed with bar codes that are used to register preferential pricing. Previous attempts at packaging a bar code reader into a fuel dispenser had several shortcomings. One such example is the use of a single scan line reader attached to an existing magnetic stripe card reader. The resulting assembly is confusing for customers attempting to determine proper card orientation for insertion and frustrating due to the lack of tolerance in reading poorly printed bar codes. Such a device is also very limited in the type or shape of bar code formats which can actually be read. Furthermore, such an arrangement is incapable of reading bar codes printed on any other media, such as receipts, coupons, or the like.
Of particular note is the PCT application entitled "Bar Code Reader for a Fuel Dispenser" published in the name of Dresser Industries, Inc. on Aug. 27, 1998 as International Application No. WO 98/37518 (hereinafter "WO 98/37518"). WO 98/37518 discloses a bar code reader system for a fuel dispenser. In its most detailed embodiment (FIG. 5), WO 98/37518 includes both a bar code reader 118 for accepting bar code encoded cards and also a front surface mounted mechanism 120 for reading other bar code media such as printed receipts and the like. Thus, WO 98/37518 requires the implementation of at least two separate optical scanning devices. Moreover, the surface mounted mechanism 120 is shaped like a cross necessitating that the customer present bar encoded media for reading in either an entirely horizontal or an entirely vertical orientation in order to successfully be read.
WO 98/37518 does not contemplate an integrated unit for reading both a very low aspect ratio bar encoded card and other bar encoded media of varying aspect ratios using a single optical scanning device. Moreover, the present invention incorporates multi-line scanning and optical equipment which allow for consistent readability of low and high aspect ratio cards. The multiline scanning and optical equipment disperses a radial scan pattern which effectively allows the customer to insert other bar encoded media into a receiving cavity without having to specifically orient the bar code with the scanning device. Lastly, the present invention includes a sensing mechanism capable of determining when a card has been inserted into the reading area or when other bar encoded media have been inserted into the receiving cavity. Upon detection of such an occurrence, then, and only then, will the system activate the optical scanning equipment. Thus, a significant reduction in mechanical wear of the optical scanning equipment is achieved since the unit is only active when necessary. It is not continuously running in anticipation of reading a bar encoded card or other bar encoded media.
Significant room for improvement therefore exists in the art of bar code readers, particularly for a system of mounting and using a bar code reader on an energy dispensing device.
The present invention consistently reads cards having a very low aspect ratio bar code placed thereon (very short stripes relative to a wide code length). Such cards may also have inconsistent and/or generally poor print quality. With this type of bar code to be read, alignment of the bar code to the scan line is critical and may only vary by a few degrees and still achieve a successful "read." This is because a scanner, with its associated deciphering algorithms, "knows" when a good read has been made by recognizing the blank space on either side of the bar code, indicating that a complete code is in between. If the scan line goes across the bar code at some skewed angle such that the scan line does not reach completely across the bar code at the same instant, a "read" will not take place.